Saturday Briefing: Knowledge is power

IS there anything you are desperately yearning to know? Are there any pressing factual disputes you would like us to help resolve? This is the page where we shall do our best to answer any questions you throw at us, whatever the subject.

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This was in great demand by Portuguese sailors who called the country “Terro do Brazil” (Land of the Brazil) because of the brazilwood trade. Brazil nuts do not come from the brazilwood tree but the Brazil nut tree, which is quite different. Most Brazil nuts, incidentally, come not from Brazil but Bolivia.

Q: Could I ask what would happen if polar bears were introduced at the South Pole and penguins were introduced at the North Pole? Would they survive and thrive or are there reasons why not? Howard Robinson, Shrewsbury

A: The main problem would be that the penguins would be eaten by the polar bears. The bears are omnivorous scavengers and penguins, which have no natural predators in Antarctica, would fall prey to them.

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Polar bears would quickly hunt penguins to extinction

To have much chance of survival we’d have to keep them apart by moving all the polar bears to the South Pole and all the Antarctic penguins to the north.

Even then, the bears would be a great danger to the seal population and the penguins would probably fall prey to other carnivores such as Arctic foxes.

It’s really a question of whether the penguins could evolve a survival strategy before they are wiped out.

The most northerly penguin colonies in fact are Galapagos penguins at the equator.

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The sand in the Sahara is approximately 500ft deep

Q: Has anyone estimated the average depth of the Sahara sand? What is its base? And what undiscovered mineral deposits may lie in that base? Norman Rendle, Cardiff

A: Various estimates have been made of the depth of dunes in the Sahara but as they are constantly changing shape it’s difficult to give an answer.

The generally accepted view is the average depth is about 500feet. Beneath the sand it is mostly bedrock but cracks and fissures in the bedrock may result in the sand being far deeper in places.

As for mineral deposits beneath the sand, oil and natural gas have been located, as well as iron ore, anthracite seams and even huge reserves of underground water.

Economic development of all these however often remains prohibitively expensive.

Queen Elizabeth II in pictures

Tue, July 3, 2018

The latest pictures of Her Majesty the Queen.

Queen Elizabeth II attends a reception for 603 (City of Edinburgh) Squadron, Royal Auxiliary Air Force

Q: My wife and I have recently become great-grandparents to a little girl. I am pleased to say that she has all eight great-grandparents still alive, married to the same partners and all in their 80s. Is it possible to estimate the odds of this happening? Dennis Johnson, Macclesfield, Cheshire

A: Remarkably it is not as unusual as you may think. Of all the people born in the UK in 1935 about 40 per cent of the men and 50 per cent of the women are still alive, so the chance of four men and four women born at that time still being alive works out at one in 625.

That calculation relies on having eight great-grandparents all in their early 80s, which means they married young and had children young.

The average age of the parents of a newborn are now 33 for men and 30 for women, which means that the average great-grandparent is at least a nonagenarian.

Around one in six of all babies are born to parents under 25 and this factor would extend our one in 625 chance to about one in a million. So congratulations!

But with more than 600,000 births in the UK every year, this happens about once every two years.

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It is unlikely the Queen will send herself a card

Q: We hope that our Queen will live to be 100 years old but if so, will she send a birthday card to herself? Mandy Grossman, Edgware, Greater London

A: To receive a 100th birthday card from the Queen one must apply to the Anniversaries Office, Buckingham Palace, London SW1A 1AA, either on one’s own behalf or someone else’s.

If you apply for someone else the Department of Work and Pensions will then approach that person to check whether they want to receive one.

The DWP may also ask for a copy of the birth certificate, though that may be unnecessary if they are in receipt of a state pension.

I don’t think that applies to the Queen and it’s unlikely she will request a card so she probably won’t be sending herself one.

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